Leonard Saxe, Ph.D., a polygraph expert and professor of Psychology at Brandeis University, says, "Lying has long been a part of everyday life. We couldn't get through the day without being deceptive." Still, most of us know the difference between a white lie and outright deceit. One study says that we lie in about a fifth of their interpersonal exchanges lasting ten or more minutes. Over the course of a week, we deceive about 30 percent of those with whom we interact one-on-one. And the closer the relationship, the more likely we are to lie. There’s evidence that some self-delusion—basically, lying to yourself—is essential to good mental health. Let’s explore the psychology behind lying and whether absolute candor would be a positive thing for either society or we as individuals.